testsuite: Introduce a new test for para_server.
[paraslash.git] / alsa_write.c
1 /*
2 * Copyright (C) 2005-2011 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file alsa_write.c paraslash's alsa output plugin */
8
9 /*
10 * Based in parts on aplay.c from the alsa-utils-1.0.8 package,
11 * Copyright (c) by Jaroslav Kysela <perex@suse.cz>, which is
12 * based on the vplay program by Michael Beck.
13 */
14
15 #include <regex.h>
16 #include <sys/types.h>
17 #include <alsa/asoundlib.h>
18 #include <sys/time.h>
19 #include <stdbool.h>
20
21 #include "para.h"
22 #include "fd.h"
23 #include "string.h"
24 #include "list.h"
25 #include "sched.h"
26 #include "ggo.h"
27 #include "buffer_tree.h"
28 #include "write.h"
29 #include "write_common.h"
30 #include "alsa_write.cmdline.h"
31 #include "error.h"
32
33 /** Data specific to the alsa writer. */
34 struct private_alsa_write_data {
35 /** The alsa handle */
36 snd_pcm_t *handle;
37 /** Determined and set by alsa_init(). */
38 int bytes_per_frame;
39 /** The approximate maximum buffer duration in us. */
40 unsigned buffer_time;
41 /* Number of frames that fit into the buffer. */
42 snd_pcm_uframes_t buffer_frames;
43 /**
44 * The sample rate given by command line option or the decoder
45 * of the writer node group.
46 */
47 unsigned sample_rate;
48 snd_pcm_format_t sample_format;
49 /**
50 * The number of channels, given by command line option or the
51 * decoder of the writer node group.
52 */
53 unsigned channels;
54 struct timeval drain_barrier;
55 /* File descriptor for select(). */
56 int poll_fd;
57 };
58
59 static snd_pcm_format_t get_alsa_pcm_format(enum sample_format sf)
60 {
61 switch (sf) {
62 case SF_S8: return SND_PCM_FORMAT_S8;
63 case SF_U8: return SND_PCM_FORMAT_U8;
64 case SF_S16_LE: return SND_PCM_FORMAT_S16_LE;
65 case SF_S16_BE: return SND_PCM_FORMAT_S16_BE;
66 case SF_U16_LE: return SND_PCM_FORMAT_U16_LE;
67 case SF_U16_BE: return SND_PCM_FORMAT_U16_BE;
68 default: return SND_PCM_FORMAT_S16_LE;
69 }
70 }
71
72 /* Install PCM software and hardware configuration. */
73 static int alsa_init(struct private_alsa_write_data *pad,
74 struct alsa_write_args_info *conf)
75 {
76 snd_pcm_hw_params_t *hwparams;
77 snd_pcm_sw_params_t *swparams;
78 snd_pcm_uframes_t start_threshold, stop_threshold;
79 snd_pcm_uframes_t period_size;
80 int err;
81
82 PARA_INFO_LOG("opening %s\n", conf->device_arg);
83 err = snd_pcm_open(&pad->handle, conf->device_arg,
84 SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
85 if (err < 0)
86 return -E_PCM_OPEN;
87
88 snd_pcm_hw_params_alloca(&hwparams);
89 snd_pcm_sw_params_alloca(&swparams);
90 if (snd_pcm_hw_params_any(pad->handle, hwparams) < 0)
91 return -E_BROKEN_CONF;
92 if (snd_pcm_hw_params_set_access(pad->handle, hwparams,
93 SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
94 return -E_ACCESS_TYPE;
95 if (snd_pcm_hw_params_set_format(pad->handle, hwparams,
96 pad->sample_format) < 0)
97 return -E_SAMPLE_FORMAT;
98 if (snd_pcm_hw_params_set_channels(pad->handle, hwparams,
99 pad->channels) < 0)
100 return -E_CHANNEL_COUNT;
101 if (snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
102 &pad->sample_rate, NULL) < 0)
103 return -E_SET_RATE;
104 err = snd_pcm_hw_params_get_buffer_time_max(hwparams,
105 &pad->buffer_time, NULL);
106 if (err < 0 || !pad->buffer_time)
107 return -E_GET_BUFFER_TIME;
108 PARA_INFO_LOG("buffer time: %d\n", pad->buffer_time);
109 if (snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
110 &pad->buffer_time, NULL) < 0)
111 return -E_SET_BUFFER_TIME;
112 if (snd_pcm_hw_params(pad->handle, hwparams) < 0)
113 return -E_HW_PARAMS;
114 snd_pcm_hw_params_get_period_size(hwparams, &period_size, NULL);
115 snd_pcm_hw_params_get_buffer_size(hwparams, &pad->buffer_frames);
116 PARA_INFO_LOG("buffer size: %lu, period_size: %lu\n", pad->buffer_frames,
117 period_size);
118 if (period_size == pad->buffer_frames)
119 return -E_BAD_PERIOD;
120 snd_pcm_sw_params_current(pad->handle, swparams);
121 snd_pcm_sw_params_set_avail_min(pad->handle, swparams, period_size);
122 if (pad->buffer_frames < 1)
123 start_threshold = 1;
124 else
125 start_threshold = PARA_MIN(pad->buffer_frames,
126 (snd_pcm_uframes_t)pad->sample_rate);
127 if (snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
128 start_threshold) < 0)
129 return -E_START_THRESHOLD;
130 stop_threshold = pad->buffer_frames;
131 if (snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
132 stop_threshold) < 0)
133 return -E_STOP_THRESHOLD;
134 if (snd_pcm_sw_params(pad->handle, swparams) < 0)
135 PARA_WARNING_LOG("unable to install sw params\n");
136 pad->bytes_per_frame = snd_pcm_format_physical_width(pad->sample_format)
137 * pad->channels / 8;
138 if (pad->bytes_per_frame <= 0)
139 return -E_PHYSICAL_WIDTH;
140 PARA_INFO_LOG("bytes per frame: %d\n", pad->bytes_per_frame);
141 if (snd_pcm_nonblock(pad->handle, 1))
142 PARA_ERROR_LOG("failed to set nonblock mode\n");
143 return 1;
144 }
145
146 static void alsa_write_pre_select(struct sched *s, struct task *t)
147 {
148 struct pollfd pfd;
149 struct writer_node *wn = container_of(t, struct writer_node, task);
150 struct private_alsa_write_data *pad = wn->private_data;
151 int ret = btr_node_status(wn->btrn, wn->min_iqs, BTR_NT_LEAF);
152
153 if (pad)
154 pad->poll_fd = -1;
155 if (ret == 0)
156 return;
157 if (!pad) {
158 sched_min_delay(s);
159 return;
160 }
161 if (ret < 0) {
162 sched_request_barrier_or_min_delay(&pad->drain_barrier, s);
163 return;
164 }
165 ret = snd_pcm_poll_descriptors(pad->handle, &pfd, 1);
166 if (ret < 0) {
167 PARA_ERROR_LOG("%s\n", snd_strerror(-ret));
168 t->error = -E_ALSA_POLL_FDS;
169 return;
170 }
171 pad->poll_fd = pfd.fd;
172 para_fd_set(pfd.fd, &s->rfds, &s->max_fileno);
173 }
174
175 static void alsa_close(struct writer_node *wn)
176 {
177 struct private_alsa_write_data *pad = wn->private_data;
178 PARA_INFO_LOG("closing writer node %p\n", wn);
179
180 if (!pad)
181 return;
182 /*
183 * It's OK to have a blocking operation here because we already made
184 * sure that the PCM output buffer is (nearly) empty.
185 */
186 snd_pcm_nonblock(pad->handle, 0);
187 snd_pcm_drain(pad->handle);
188 snd_pcm_close(pad->handle);
189 snd_config_update_free_global();
190 free(pad);
191 }
192
193 static void alsa_write_post_select(__a_unused struct sched *s,
194 struct task *t)
195 {
196 struct writer_node *wn = container_of(t, struct writer_node, task);
197 struct private_alsa_write_data *pad = wn->private_data;
198 struct btr_node *btrn = wn->btrn;
199 char *data;
200 size_t bytes;
201 snd_pcm_sframes_t frames;
202 int ret;
203
204 again:
205 t->error = 0;
206 ret = btr_node_status(btrn, wn->min_iqs, BTR_NT_LEAF);
207 if (ret == 0)
208 return;
209 btr_merge(btrn, wn->min_iqs);
210 bytes = btr_next_buffer(btrn, &data);
211 if (ret < 0 || bytes < wn->min_iqs) { /* eof */
212 assert(btr_no_parent(btrn));
213 ret = -E_WRITE_COMMON_EOF;
214 if (!pad)
215 goto err;
216 /* wait until pending frames are played */
217 if (pad->drain_barrier.tv_sec == 0) {
218 PARA_DEBUG_LOG("waiting for device to drain\n");
219 tv_add(now, &(struct timeval)EMBRACE(0, 200 * 1000),
220 &pad->drain_barrier);
221 return;
222 }
223 if (tv_diff(now, &pad->drain_barrier, NULL) > 0)
224 goto err;
225 return;
226 }
227 if (!pad) {
228 int32_t val;
229
230 if (bytes == 0) /* no data available */
231 return;
232 pad = para_calloc(sizeof(*pad));
233 get_btr_sample_rate(btrn, &val);
234 pad->sample_rate = val;
235 get_btr_channels(btrn, &val);
236 pad->channels = val;
237 get_btr_sample_format(btrn, &val);
238 pad->sample_format = get_alsa_pcm_format(val);
239
240 PARA_INFO_LOG("%d channel(s), %dHz\n", pad->channels,
241 pad->sample_rate);
242 ret = alsa_init(pad, wn->conf);
243 if (ret < 0) {
244 free(pad);
245 goto err;
246 }
247 wn->private_data = pad;
248 wn->min_iqs = pad->bytes_per_frame;
249 goto again;
250 }
251 if (pad->poll_fd >= 0 && !FD_ISSET(pad->poll_fd, &s->rfds))
252 return;
253 frames = bytes / pad->bytes_per_frame;
254 frames = snd_pcm_writei(pad->handle, data, frames);
255 if (frames == 0 || frames == -EAGAIN)
256 return;
257 if (frames > 0) {
258 btr_consume(btrn, frames * pad->bytes_per_frame);
259 goto again;
260 }
261 if (frames == -EPIPE) {
262 PARA_WARNING_LOG("underrun (tried to write %zu bytes)\n", bytes);
263 snd_pcm_prepare(pad->handle);
264 return;
265 }
266 PARA_WARNING_LOG("%s\n", snd_strerror(-frames));
267 ret = -E_ALSA_WRITE;
268 err:
269 assert(ret < 0);
270 btr_remove_node(btrn);
271 t->error = ret;
272 }
273
274 __malloc static void *alsa_parse_config_or_die(const char *options)
275 {
276 struct alsa_write_args_info *conf = para_calloc(sizeof(*conf));
277
278 /* exits on errors */
279 alsa_cmdline_parser_string(options, conf, "alsa_write");
280 return conf;
281 }
282
283 static void alsa_free_config(void *conf)
284 {
285 alsa_cmdline_parser_free(conf);
286 }
287
288 /**
289 * The init function of the alsa writer.
290 *
291 * \param w Pointer to the writer to initialize.
292 *
293 * \sa struct \ref writer.
294 */
295 void alsa_write_init(struct writer *w)
296 {
297 struct alsa_write_args_info dummy;
298
299 alsa_cmdline_parser_init(&dummy);
300 w->close = alsa_close;
301 w->pre_select = alsa_write_pre_select;
302 w->post_select = alsa_write_post_select;
303 w->parse_config_or_die = alsa_parse_config_or_die;
304 w->shutdown = NULL; /* nothing to do */
305 w->free_config = alsa_free_config;
306 w->help = (struct ggo_help) {
307 .short_help = alsa_write_args_info_help,
308 .detailed_help = alsa_write_args_info_detailed_help
309 };
310 alsa_cmdline_parser_free(&dummy);
311 }